# Prompt Variable Filler

> Paste a template prompt and fill every {{variable}}, {variable}, [INSERT …] and [CAPS] slot from one form. Free, private, runs in your browser.

Canonical: https://promptitin.com/free-tools/prompt-variable-filler
Last updated: 2026-11-13

Template prompts are full of blanks. Paste one here and every blank becomes a box. Fill them in once and copy the finished prompt.

This is an interactive tool. Use it at https://promptitin.com/free-tools/prompt-variable-filler.

## How to use it

1. Paste a template prompt, or tap Try an example.
2. Fill in the box for each slot it finds.
3. Watch the finished prompt update below as you type.
4. Copy it, or send it to PromptItIn to improve it.

## Tips

- Slots with the same name are filled together, so {company} used three times needs one answer.
- Leave a box empty to keep that slot as it is.
- Works with prompts from our prompt library, which use [INSERT …] slots.
- Save templates you reuse with your own {{variables}} so they're quick to fill next time.

## FAQ

### Which slot styles does it find?

Double braces like {{topic}}, single braces like {topic}, [INSERT topic] and words in capitals inside square brackets like [PRODUCT NAME].

### Will it break JSON or Markdown links?

No. Braces with quotes or colons inside and normal [link text](url) are left alone.

### Is my prompt sent anywhere?

No. Everything happens in your browser. Nothing leaves your device unless you choose to open it in PromptItIn.

### Is it free?

Yes. No account, no limit.

## Related

- [Prompt Framework Builder](https://promptitin.com/free-tools/prompt-framework-builder)
- [Prompt Grader](https://promptitin.com/free-tools/prompt-grader)
- [AI Token Counter](https://promptitin.com/free-tools/ai-token-counter)